Calcium absorption not the cause of evolution of milk digestion in Europeans – “‘The evolution of lactase persistence is one of the best known and most dramatic examples of recent human evolution. One of the ironies of working in this area is that we know it happened but we still don’t fully know why’ says Sverrisdóttir. Lactase persistence is found at highest frequencies in southern Sweden and in Ireland. Given that calcium absorption is not the only reason why this trait evolved so rapidly, Sverrisdóttir and colleagues have proposed another cause: Although most early European farmers would not have been lactase persistent, they would still have been able to consume fermented milk products such as yoghurt and cheese, because fermentation converts much of the lactose into fats. But in famine conditions, such as when crops fail, they are likely to have eaten all the fermented milk foods, leaving only the more high-lactose products. This would have caused the usual lactose intolerance symptoms such as diarrhea. Diarrhea in in healthy people is not usually life-threatening, but in severely malnourished individuals it certainly can be. So famine could have led to episodes of very strong natural selection favoring lactase persistence.”

Human and Helicobacter pylori coevolution shapes the risk of gastric disease – “Patients were recruited from two geographically distinct Colombian populations with significantly different incidences of gastric cancer, but virtually identical prevalence of H. pylori infection. All H. pylori isolates contained the genetic signatures of multiple ancestries, with an ancestral African cluster predominating in a low-risk, coastal population and a European cluster in a high-risk, mountain population. The human ancestry of the biopsied individuals also varied with geography, with mostly African ancestry in the coastal region (58%), and mostly Amerindian ancestry in the mountain region (67%). The interaction between the host and pathogen ancestries completely accounted for the difference in the severity of gastric lesions in the two regions of Colombia. In particular, African H. pylori ancestry was relatively benign in humans of African ancestry but was deleterious in individuals with substantial Amerindian ancestry. Thus, coevolution likely modulated disease risk, and the disruption of coevolved human and H. pylori genomes can explain the high incidence of gastric disease in the mountain population.”

Seeing X Chromosomes in a New Light – “X-chromosome inactivation, Dr. Nathans’s pictures show, creates a genetic diversity that’s particularly dramatic. Two cells side by side may be using different versions of many different genes. ‘But there is also much larger-scale diversity,’ Dr. Nathans said. In some brains, for example, a mother’s X chromosome was seen dominating the left side, while the father’s dominated the right. Entire organs can be skewed toward one parent. Dr. Nathans and his colleagues found that in some mice, one eye was dominated by the father and the other by the mother. The diversity even extended to the entire mouse. In some animals, almost all the X chromosomes from one parent were shut; in others, the opposite was true.”

Are plants altruistic? – “Roots can distinguish self from other, and they know their own kind (species), they can share resources and information about insect attacks and deliver nutrients to trees in need. The preponderance of evidence does seem to suggest that plants are proactive in filling their own needs and the needs of others.” – ooooh, not just their own species, their own close relatives! – see also The Intelligent Plant.

Sluggish metabolisms are key to primates’ long lives – “[P]rimates expend 50 per cent less energy than other mammals of equivalent mass during an average day. ‘What’s more, he says the difference is not easily explained by differing activity levels: a human would need to run a whole marathon every day to be on an even energetic footing with mammals that aren’t primates….’ The finding offers a completely new way to understand why primates have slower life histories than other mammals of equivalent body size…. Pontzer thinks that the slower metabolism may have evolved to help primates cope with food shortages. For instance, orang-utans suffer frequent famines. ‘Orang-utans experience extended periods of low fruit availability,’ says Vogel. ‘There are months when caloric intake is less than expenditure – and they burn body fat stores.’ A slow metabolism might help them survive.”

Triune origins – “With the latest paper, the story on European origins is becoming clearer. Three populations account for European ancestry: the Mesolithic hunter-gatherers of western Europe (dubbed WHG in the paper), early European farmers derived from somewhere in the Mideast (EEF), and a third group more closely related to ancient Siberians (ANE) than any existing population. Those Sibermen also contributed a third of Amerindian ancestry, the rest being similar to modern East Asian populations.” – from greg cochran.

The first industrial revolution – “As early modern humans spread farther north, they entered more challenging environments…. Did these new cognitive demands have an evolutionary impact? Did they select for certain mental capacities over others? Piffer (2013) has addressed these questions by seeing how hunter-gatherers differ from farming peoples in alleles at COMT, a gene linked to executive function, working memory, and intelligence…. Northern hunting peoples, however, differ from other hunter-gatherers and resemble more advanced farming populations.” – from peter frost.

Changes in Thickness and Surface Area of the Human Cortex and Their Relationship with Intelligence – “At 10 years of age, more intelligent children have a slightly thinner cortex than children with a lower IQ. This relationship becomes more pronounced with increasing age: with higher IQ, a faster thinning of the cortex is found over time. In the more intelligent young adults, this relationship reverses so that by the age of 42 a thicker cortex is associated with higher intelligence. In contrast, cortical surface is larger in more intelligent children at the age of 10. The cortical surface is still expanding, reaching its maximum area during adolescence. With higher IQ, cortical expansion is completed at a younger age; and once completed, surface area decreases at a higher rate. These findings suggest that intelligence may be more related to the magnitude and timing of changes in brain structure during development than to brain structure per se, and that the cortex is never completed but shows continuing intelligence-dependent development.”

Why do spatial abilities predict mathematical performance? – “About a third of the variation in spatial ability at age 12 is explained by genetic factors; a little less than half of the variation in mathematics at this age is genetic. We find no sex differences in the genetic and environmental influences (either in magnitude or type) on mathematical and spatial variation at age 12. The observed overlap between spatial ability and mathematics is substantial (r > .40). Approximately 60% of this overlap is explained by common genetic effects, with 40% of the overlap due to environmental experience.” – h/t DOCTOR stuart ritchie! (^_^)

New evidence shows the FDA was wrong to halt 23andMe testing – “While the tests are often too inaccurate for consumers to consider them diagnoses, research shows that most customers will seek a doctor’s opinion before taking action, anyway. According to the authors’ research, 58% of 1,051 surveyed customers did nothing at all with their genomic results. Of the 42% who made health decisions based on the information, only 2% changed prescription drug regimens without consulting a physician. The majority of customers who made changes focused on diet, exercise, and vitamins.”

Dogs’ Closest Wolf Ancestors Went Extinct, Study Suggests – ” A new genetic analysis of modern dogs and wolves suggests that man’s best friend was domesticated before agriculture. But the origin of this domestication remains stubbornly mysterious. Researchers analyzed the genomes of wolves from three likely sites of domestication (the Middle East, Asia and eastern Europe), and found that modern dogs were not more closely related to any of the three. In fact, it seems that the closest wolf ancestors of today’s dogs may have gone extinct, leaving no wild descendants.” – also: Paedomorphic Facial Expressions Give Dogs a Selective Advantage – woof! – h/t claire lehmann!

Eye of the Tiger People – “But what the hell is ‘culture,’ anyway? Talk about a social construct! Even the term ‘social construct’ is a social construct, one unique to our culture. And who’s to say culture is entirely separate from genetics? There’s some suggestion that the two may be intimately intertwined. In rawest terms, ‘culture’ may be nothing more than what happens when a group’s genes interact with their environment.“ – from jim goad.

Toddlers’ aggression is strongly associated with genetic factors, study reports – “The development of physical aggression in toddlers is strongly associated genetic factors and to a lesser degree with the environment, according to a new study led by Eric Lacourse of the University of Montreal and its affiliated CHU Sainte-Justine Hospital. Lacourse’s worked with the parents of identical and non-identical twins to evaluate and compare their behaviour, environment and genetics.” – h/t mr. mangan, esq!

Apes are intuitive statisticians – “Here, we conducted the first investigation of such intuitive statistical reasoning with non-human primates. In a series of 7 experiments, Bonobos, Chimpanzees, Gorillas and Orangutans drew flexible statistical inferences from populations to samples. These inferences, furthermore, were truly based on statistical information regarding the relative frequency distributions in a population, and not on absolute frequencies. Intuitive statistics in its most basic form is thus an evolutionarily more ancient rather than a uniquely human capacity.” – iow, the other great apes outperform a lot of humans (i.e. the pc ones)! (~_^) – h/t neuroskeptic!

Comedians have psychotic personality traits, study finds – “In a study in the British Journal of Psychiatry, researchers analyzed comedians from Australia, Britain and the United States and found they scored significantly higher on four types of psychotic characteristics compared to a control group of people who had non-creative jobs. The traits included a tendency towards impulsive or anti-social behavior, and a tendency to avoid intimacy. ‘The creative elements needed to produce humor are strikingly similar to those characterizing the cognitive style of people with psychosis – both schizophrenia and bipolar disorder,’ said Gordon Claridge of the University of Oxford’s department of experimental psychology, who led the study.”

New study finds mistimed sleep disrupts rhythms of genes in humans – “During this disruption of sleep timing, there was a six-fold reduction in the number of genes that displayed a circadian rhythm (a rhythm with an approximately 24 hour period). This included many regulators associated with transcription and translation, indicating widespread disruption to many biological processes.” – sleep right!

The Islamic Republic of Baby-Making – “Iran, like other Middle Eastern countries, has an extremely high infertility rate. More than 20 percent of Iranian couples cannot conceive, according to a study conducted by one of the country’s leading fertility clinics, compared with the global rate of between 8 and 12 percent. Experts believe this is due to the prevalence of consanguineous marriages, or those between cousins. Male infertility is ‘the hidden story of the Middle East,’ says Marcia Inhorn, a Yale University medical anthropologist and a specialist on assisted reproduction in the region.”

Gene therapy ‘could be used to treat blindness’ – “Surgeons in Oxford have used a gene therapy technique to improve the vision of six patients who would otherwise have gone blind. The operation involved inserting a gene into the eye, a treatment that revived light-detecting cells.”

Deletion of Any Single Gene Provokes Mutations Elsewhere in the Genome – “Johns Hopkins researchers report that the deletion of any single gene in yeast cells puts pressure on the organism’s genome to compensate, leading to a mutation in another gene…. ‘The deletion of any given gene usually results in one, or sometimes two, specific genes being “warped” in response….'”

Europeans and South Asians share by descent SLC24A5 light skin allele – “‘We date the coalescence of the light skin associated allele at 22–28 KYA. Both our sequence and genome-wide genotype data confirm that this gene has been a target for positive selection among Europeans. However, the latter also shows additional evidence of selection in populations of the Middle East, Central Asia, Pakistan and North India but not in South India.'” – @dienekes’.

The ancestors with no descendants – “On the eve of the last ice age, Siberia was home to a people who were related to modern Europeans and Amerindians but not to modern native Siberians. So concludes an analysis of DNA from the remains of a boy who lived 24,000 years ago at Mal’ta near Lake Baikal, Siberia…. [T]he Mal’ta people probably looked very much like native Indians with a more European skull shape, perhaps like the Ainu of northern Japan or the Kennewick humans of North America.”

Political colour is half genetic – “New study provides definitive evidence that heritability plays a significant role in the formation of political ideology, regardless of how ideology is measured, the time period or population sampled.” – @ScienceNordic.com – the photo caption is pretty funny/telling: “Imagine if scientists could identify the ‘liberal’ genes and genetically modify babies so that they all voted liberal when they grow up? Brave new world?” (and the first comment is priceless!) – h/t ray sawhill!

It’s not just conservatives that support discrimination against their ideological foes – “‘Discrimination by liberals has received scant attention in the literature, despite this being a prevalent concern in conservative rhetoric. By only examining conservative biases, social scientists fail to fully explore political intolerance in America. This research helps fill that gap….’ When opposing groups were seen as violating core values, liberals were just as likely to support discrimination against same-sex marriage opponents, religious fundamentalists, Tea Party protestors, and prolife people as were conservatives against feminists, atheists, leftist protestors, and prochoice people.”

Study: Your brain sees things you don’t – “Our brains perceive objects in everyday life of which we may never be aware, a study finds, challenging currently accepted models about how the brain processes visual information.”

Religions of the American Nations – “[T]hese differences [regional cultural and political divisions in america] stem from the *genetic* differences in the descendants of these initial settlers (suffused with the genes of subsequent immigrants, particularly in the old North).” – from jayman.

In Hookups, Inequality Still Reigns – “[A] study of 24,000 students at 21 colleges over five years found that about 40 percent of women had an orgasm during their last hookup involving intercourse, while 80 percent of men did.” – h/t john durant!

The Co-Villains Behind Obesity’s Rise – “Not everyone, however, has the same gut bacteria. And, interestingly, the composition of this bacteria correlates with obesity…. [T]he bacteria study found that the ‘obese gut bacteria’ had an impact only when the mice were fed diets heavy in saturated fats.” – h/t jayman!

Rich Chinese Couples Turning To American Surrogates For Easier Immigration And ‘Designer Babies’ – “Another factor that has some Chinese couples choosing American surrogates is a desire for ‘designer babies.’ While most couples still use their own eggs and sperm, making the child biologically theirs, Reuters reports that more and more people are open to egg donation, to get what some clients believe are smarter and better-looking children. ‘Lots of clients that are Chinese do use tall, blond donors,’ Jennifer Garcia, who works at Extraordinary Conception in California, where 40 percent of clients are Chinese, said in the report.” – h/t mark krikorian!

Should state education be abolished? – “New York City adopting Finland’s education system is not going to make New York like Finland…. In the game of life the dice are loaded and trying to make teachers responsible for making life fair is deluded and unfair to them….” – from ed west.

John Derbyshire’s Modest Proposal On Politics and Intelligence – “And the too-dumb-to-vote segment is only a part of the problem we conservatives have with universal suffrage. Here’s another part: too *smart* to vote…. At the very highest levels of intelligence, the correlation between IQ and sensible political opinions may actually be *inverse*: the more brilliant you are, the dumber your politics. Albert Einstein thought well of Stalin; Hitlerism got its first mass following in the highly-selective German universities.”

bonus: Another Word for “Holocaust” – “[O]ne would have to be smoking banana peels dipped in formaldehyde and sprinkled with PCP to assert that both events [the holocaust and the holodomor] receive a similar amount of attention in Western media and academia.” – from jim goad. of course.

bonus bonus: Swedish cinemas launch feminist movie rating – hahahahahaha!!! heh. wait. (*hbd chick wipes tears from eyes*) heh. – “To get an ‘A’ rating, a movie must pass the so-called Bechdel test, which means it must have at least two named female characters who talk to each other about something other than a man….” – hahahahahaha!! – “The entire ‘Lord of the Rings’ trilogy, all ‘Star Wars’ movies, ‘The Social Network,’ ‘Pulp Fiction’ and all but one of the ‘Harry Potter’ movies fail this test,” – so, except for The Social Network, all of my faves. this is going to be a REALLY handy movie rating system. whatever movies they FAIL, i will go see! (^_^)

bonus bonus bonus: Strange Doings on the Sun – “Sunspots, Which Can Harm Electronics on Earth, Are Half the Number Expected” – ruh roh.

Misguided Nostalgia for Our Paleo Past – “Gregory Cochran and Henry Harpending even suggest that human evolution as a whole has, on the contrary, accelerated over the last several thousand years, and they also believe that relatively isolated groups of people, such as Africans and North Americans, are subject to differing selection. That leads to the somewhat uncomfortable suggestion that such groups might be evolving in different directions—a controversial notion to say the least.” – i dunno why that suggestion should be uncomfortable, but i guess it is. -?- see also steve sailer.

Mediterranean Diet Cuts Heart Disease Risk – IN MEDITERRANEAN PEOPLE! – “Heart disease experts said the study was a triumph because it showed that a diet was powerful in reducing heart disease risk, and it did so using the most rigorous methods. Scientists randomly assigned 7,447 people in Spain who were overweight, were smokers, or had diabetes or other risk factors for heart disease to follow the Mediterranean diet or a low-fat one.” – *facepalm*

The sociology of dysgenia – “Eugenics is a great idea, and perhaps it’s not as complex as I make it to be here. But the fact remains that for all we speculate, we know very, very little about it.” – from spandrell. via foseti.

Can India’s Democracy Defeat Corruption? – “Of course, big corruption scandals are commonplace in the developing world (and the developed world, for that matter). Yet the scale and relative peacefulness of the corruption debate in India may be unprecedented…. And although the Indian political system is imperfect in ways too numerous to list here, the central authorities most of the time do respect free speech and free press. Civil society works. Freedom of association works….”

bonus: The Big Question – “Q: What day most changed the course of history?” – i like freeman dyson’s response. (^_^)

bonus bonus: Dolphins Call Each Other By Name – “Bottlenose dolphins call out the specific names of loved ones when they become separated, a study finds. Other than humans, the dolphins are the only animals known to do this….”

Ethnic disparities in breast cancer survival remain despite socioeconomic similarities – “All-cause survival was worse for African-Americans and better for Latinas and Asian-Americans compared with non-Latina whites after adjusting for age, study and tumor characteristics. When the researchers additionally adjusted for treatment and reproductive and lifestyle factors, they found that African-Americans had similar survival rates to non-Latina whites, but the survival rates of Latinas and Asian-Americans remained better.”

A detour through Europe? – “The lithic technology of southwestern France (c. 22,000-17,000 BP) strangely resembles that of the first paleo-Amerindians (c. 12,000). Some people speculate that early Europeans reached North America by crossing the Atlantic. The truth is even more incredible. Early Europeans spread eastward and became the ancestors not only of the Amerindians but also of East Asians.” – from peter frost.

The Island Where People Forget to Die – “[P]eople on Ikaria were, in fact, reaching the age of 90 at two and a half times the rate Americans do. (Ikarian men in particular are nearly four times as likely as their American counterparts to reach 90, often in better health.) But more than that, they were also living about 8 to 10 years longer before succumbing to cancers and cardiovascular disease, and they suffered less depression and about a quarter the rate of dementia.”